When I encounter an unfamiliar intelligence term, an odd acronym or a reference to an obscure office somewhere in the bowels of U.S. intelligence, I find that Richelson’s book more often than not — more often than Google — provides the explanation and the needed background, typically with a footnote to an official source.

The latest edition includes new material on homeland security intelligence, detainee interrogation, and other post-9/11 developments.